Tachykinin signaling inhibits task-specific behavioral responsiveness in honeybee workers
Behavioral specialization is key to the success of social insects and leads to division of labor among colony members. Response thresholds to task-specific stimuli are thought to proximally regulate behavioral specialization but their neurobiological regulation is complex and not well-understood. Here, we show that response thresholds to task-relevant stimuli correspond to the specialization of three behavioral phenotypes of honeybee workers in the well-studied and important Apis mellifera and Apis cerana. Quantitative neuropeptidome comparisons suggest two tachykinin-related peptides (TRP2 and TRP3) as candidates for the modification of these response thresholds. Based on our characterization of their receptor binding and downstream signaling, we confirm a functional role of tachykinin signaling in regulating specific responsiveness of honeybee workers: TRP2 injection and RNAi-mediated downregulation cause consistent, opposite effects on responsiveness to task-specific stimuli of each behaviorally specialized phenotype but not to stimuli that are unrelated to their tasks. Thus, our study demonstrates that TRP-signaling regulates the degree of task-specific responsiveness of specialized honeybee workers and may control the context-specificity of behavior in animals more generally.
Original data have been deposited to ProteomeXchange Consortium with the dataset identifier PXD018713 under http://proteomecentral.proteomexchange.org or are provided as supplementary data files.
Honeybee brain neuropeptides LC-MSMSProteomeXchange, PXD018713.
Article and author information
National Natural Science Foundation of China (31970428)
- Bin Han
Agricultural Science and Technology Innovation Program (CAAS-ASTIP-2015-IAR)
- Jianke li
National Project for Upgrading the Beekeeping Industry of China
- Jianke li
Modern Agro-Industry Technology Research System (CARS-44)
- Jianke li
University of North Carolina at Greensboro
- Olav Rueppell
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Sonia Sen, Tata Institute for Genetics and Society, India
- Received: November 12, 2020
- Accepted: March 23, 2021
- Accepted Manuscript published: March 24, 2021 (version 1)
- Version of Record published: March 31, 2021 (version 2)
© 2021, Han et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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